Pneumatic saw and the like



May 29, 1951 R. D. voN SEGGERN PNEUMATIC sAw AND THE LIKE Filed March 7, 1945 NNNN. QW v W s EN /S d N@ ER n am S N o. V. Dv. Dn Y B '.NEVNNN I :1

d .L NT o? i Patented May 29, 1953?;

UNITED E-S PAT EN T O F F l CE PNEUMA-TIo-sAW AND THE LIKE 'Roy Von' Se'ggern, Los Angeles, Calif.

Application `March 7, 1945, Serial No. 581,390

v 4 claims. .I invention relates' toV a pneumatic tool. C1165 f the; piiipal Objects. Of this invention is 'to pro-vde a pneumatic' tool, particularly fadpted to hack S'WS, vles', and the like, which."

particularly" snilpi@ and economical of corifstructon, and which is" sir'r'iple to 'manipulate and operate.

Although the terni pneumatic, when applied to rmy' tooilis used', it is" to be understood that certain features of my invention may be also fapplied to. and i's interpreted to be applied to, hydraulically operated tools; l

An important O'bject also Of this ivtion is to provide a tool o'f this class which'` may b' rmadelrelatively small andv provided with anhand I'g'rip at the side and with the desired tool' 'pro--v 'jecting from' one' end.

A'furtherimportantt objec't'o'f this invention isA to`v provide a simple valve'y mechanism for va tool of" this class; one whereby' thetool Amay easilyV andi `e'co'ri'oni'ic'all'fy made, and' one which may" beu also easily"- cleaned.- I

Still.v another' important object" of: this inven tion is to provide sin'fiple ine'ansfor pos'itively"'f locating?` the valves' inv extremey positions to` allow intake-and exhaust vof theoperating fluid;

With" these'andy other objects in View; as will appear hereinafter; I have devised a pneumatic tool having certain novel features o't construction; combination, and arrangement of parts and portions; aswill-behereinafter described in-detailand particularly set forth` in the appended claims, reference being had tothe# accompanyingfdrawings, `andto the characters of reference thereon-which Vforrn a part of this application, int-which:

Fig.; l-is a longitudinal sectional view of rny` pneufniaticv-'tool,in4 one form, a portion of the pressure. hose and. the tool being broken away;

and `4'-4'of Fig.' 1`; Fig. 5 is afragien'tary longitudinal sectional view thereof; inta1 slightly 'rnodied' form of Y'con-v structioni l 1 Thetool lillustrated Vis'v built around aj central memberv I which willbe hereafter referred to asthevalve head.' Fromt onefsid'e ofthe head secured? tri-'externally threaded endsfof the'lhead.

6. These pistons may consist of cup leathers 5a and 6a which are secured between washers 5b and 5C for the piston 5, `and Sb and (ic for the piston 6. These pistons are axially connected, the piston being screwably secured to a threaded portion 'la at the rear end of the piston rod 'I and the piston 5 being secured to a threaded inner end 8a of the tool supporting arm 8.` The inner end of the arm 8 is screwably connected to the forward end of the piston rod 'I.` The threaded portions 'Ia and 3a permit axial adJ'lIStn ment of the pistons with respect to each other for varying the stroke of the mechanism.

The motive power, which in this instance may be compressed air, is supplied from the lower end oi' the pivotal grip through, a passage 2a, there being shown an air hose 9 tted to the lower end of the pistol grip. The air from the passage 2a is connected to a distributing charnber Ia within the head I. The ends of the distributing chamber are connected by intake passages lb and Ic to the adjacent ends of the cylinders 3 and 4. Each of these intake passages consist of transverse portions Id and Ie which are connected to the cylinders 3 and 4 at their inner ends by portions which are parallel to the axis of the head. The transverse portions of the passages are intercepted by a cylindrical khere If in which is reciprocally mounted a cylin- CE1-ical intake valve II, in thevform of a rod.

The cylinders 3 and Il are connected to the atmosphere by exhaust ports Ig and Ih. These exhaust ports also consist of transverse portions Ij and Ik, respectively, which extend inwardly from the peripheral portion of the head land which are connected at their inner ends by other portions extending parallel to the axis of the head. The transverse portions Ij and Ik are also :intercepted by a cylindrical bore Im extending `-.nula-r channels I2E and I2b, these annular chjannes allowing through or clear passage of fluid through thefintake and exhaust passage.

When the valves are in the position shown by solid-lines in Fig. l' airis allowed to enter cylinder 3 by'thechannel l la through the intake port Ib. In the same position of the valves, the air from the cylinder is allowed to be exhausted through the passage lh past the channel l2b. When the valves are shifted to other positions, the passage l lb permits air to enter the cylinder ll through the port le and the channel I2a permits the air in the cylinder 3 to be exhausted through the passage Ig.

The portions of the valves intermediate the annular channels therein are provided with annular grooves, designated llc and l2c into which are forced, by means of springs l5 and i6, balls l1 and Hl, respectively, these balls locating the valves in proper positions for sequentially admitting air to the cylinders and exhausting the air from the other cylinders.

The valves H and l2 are shifted to their extreme positions by the pistons 5 and 6 when the same are moved to their inner positions. To obviate shock to the valves, I have provided concealed compression springs I9 and 2E) around the piston rod, or, as shown, around the inner end of the arm and the outer end of the piston rod l, these springs being held against the inner sides of the pistons 5 and G. These springs engage the outer sides and axial portions of the crossheads i3 and lll in order to reciproca-te the valves. The arm 8 is preferably square of crossseotion and extends through a square hole in the body 3-- so as to prevent the arm, and the tool carried thereby, from turning. As shown, there is provided a socket member 2l screwably secured to the outer end of the arm 8, and the tool, which is here shown as a hack saw blade, is detachably secured to the member 2l.

The pistol grip 2 is provided with a trigger for operating the tool by one of the fingers of the hand gripping the handle 2. This trigger is shown as a valve mechanism carried in a cylinder 3|. In the cylinder is reciprocally mounted a valve 32 having a port 32a adapted to be aligned with the passage 2a. Axially extending from one end of the cylinder 32 is a cup-shaped button 33, and between the button and a wall 3la is a compression spring 34 for holding the button in an outward position.

In the modied structure, shown in Fig. 5, I have incorporated the intake and exhaust valve means in a single reciprocating cylinder valve 42, and this valve is provided with four annular channels 42a, 42h, 420 and 42d, the rst two serving as intake channels for controlling the intake passages Ib and Ic, and the latter two controlling the exhaust passages Ig and lh.

This modified structure also eliminates one of the valve locating means, only one ball il being shown.

This modified structure has end plates 43 and 44 secured to the opposite ends of the valve 42 instead of the crosshead above described.

Though I have shown and described a particular construction, combination, and arrangement of parts and portions, and a certain modication thereof, I do not wish to be limited to the same, but desire to include in the scope of my invention the construction, combination, and arrangement, substantially as set forth in the appended claims.

I claim:

1. In a mechanism of the class described, a valve head, aligned cylinders extending from opposite ends of the head, a piston in each cylinder, means connecting the pistons, the head having a cylindrica1 bore connecting the cylinders, a cylindrical valve reciprocally mounted in the bore and shiftable into opposed operative positions therein, the head having intake passages connected to each cylinder and intercepted by the bore, and exhaust passages connecting each cylinder with the atmosphere, and also intercepted by the bore, said valve having pairs of transverse intake and exhaust channels, the intake channel of one pair allowing clear passage of fluid through the inlet passage of one cylinder and the exhaust channel of the other pair allowing clear passage of fluid through the exhaust passage of the other cylinder when the valve is in one position and alternately allowing clear passage of fluid through the other inlet and exhaust passages when the valve is in the opposite position, and means in association with the pistons for shifting the valve into said opposed positions.

2. In a mechanism of the class described, a valve head, aligned cylinders extending from opposite ends of the head, a piston in each cylinder, means connecting the pistons, the head having cylindrical bore means connecting the cylinders, a cylindrical Valve means reciprocally mounted in the bore means and shiftable4 into opposed operative position therein, the head havingintake passages connected to each'cylinder and intercepted by the bore means, and exhaust passages connecting each cylinder with the atmosphere, and also intercepted by the bore means, said valve means having pairs of trans-- verse intake and exhaust channels, the intake channel of one pair allowing clear passage of fluid through the inlet passage of one cylinder and the exhaust channel of the other pair allowing clear passage of fluid through the exhaust passage of the other cylinder when the valve means is in one position and alternately allowing clear passage of uid through the other inlet' and exhaust passages when valve means is in the opposite position, and means in association with the pistons for shifting the valve means into said opposed positions.

3. In a mechanism of the class described, a valve head, cylinders extending from the opposite end of the head, a piston in each cylinder,

means connecting the pistons, the head having a bore connecting the cylinders, a valve reciprocally mounted in the bore and shiftable into opposed operative positions, the head having a uid intake at one side and transverse intake passages connected with the fluid intake, the opposite inner l ends of the intake passages being connected by l substantially right angle portions with each cylinder, the transverse portions of the intake passages being intercepted by the bore, the head having transverse exhaust passages extending into the head from the outer portion thereof, the inner ends of the transverse exhaustl passages being connected by substantially right angle por- 4 opposite position, and means in association With asaols the pistons for shifting the valve into said opposed positions. -l

4. In a machine of the class described, a valve head, cylinders extending from `the opposite end of the head, a piston in each cylinder, means connecting the pistons, the head having a cylindrical bore means connecting thejcylinders, a valve means reciprocally mounted in the bore means and shiftable into opposed operative positions, the head having a uid intake at one side and transverse intake passages connected with the iluid intake, the opposite inner ends of the intake passages being connected by substantially right angle portions with each cylinder, the transverse portions of the intake passages being intercepted by the bore means, the head having transverse exhaust passages extendingV into'` the head from the outer portion thereof, theV inner ends of the transverse exhaust passages being connected by substantially right angle portions with each of the cylinders, the transverse portions of the exhaust passages being intercepted by the bore means, said valve means having pairs of transverse intake and exhaust channels, the intake channel of one pair allowing clear passage of iiuid through the inlet passage of one cylinder and the exhaust channel of the other pair allowing clear passage of fluid through the exhaust passage of the other cylinder lwhen the valve means is in one position and alternately allow- REFERENCES CITED The following references are of record in the tile of this patent:

UNITED sTATEs PATENTS s Number Name Date V274,879 Barton et al Mar. 27, 1883 Y `785,324 Norling Mar. 21, 1905 Y 840,886 Wilkins Jan. 8, 1907 j 935,634 Baxter Oct. 5, 1909 984,112 Schumacher Feb. 14, 1911 1,117,884 Montgomery Nov. 17, 1914 V.1,306,395 Abrams June 10, 1919 1,347,444 Christiansen July 20, 1920 1,441,017 Mattson et al Jan. 2, 1923 1,839,540 Farr Jan. 5, 1932 FOREIGN PATENTS Number Country Date 419,995 Great Britain Nov. 22, 1934 596,090 Germany Apr. 26, 1934 138,398 Switzerland May 1, 1930 

